Stem construction in a calendar watch

ABSTRACT

A watch stem in a calendar watch has a number of grooves thereon. One end of a spring, fastened at the other end to a base plate, is seated resiliently in one of the grooves. Movement of the watch stem in an axial direction requires that the seated end of the spring ride up on the walls of the grooves which are tapered. The resistance which must be overcome in moving the watch stem from one position to another can be varied by changing the angle of the groove walls and by changing the height of the walls between adjacent grooves.

United States Patent [191 Miyasaka [451 Jan. 2, 1973 [54] STEM CONSTRUCTION IN A CALENDAR WATCH [75] Inventor Marinara" Mariana; Nagafib-iren.

Japan [73] Assignee: Kabushiki Kaisha Suwa Seikasha,

[22] Filed: July 27, 1972 [21] Appl. No.: 166,373

[30] Foreign Application Priority Data July 30, 1970 Japan ..45/75485 [52] US. Cl ..58/58, 58/99 [51] Int. Cl. ..G04b 19/24, G041) 37/116 [58] Field ofSearch 58/1, 82 R, 82 A; 235/195 [56] References Cited UNITED STATES PATENTS 913,759 4/1909 Matalene... ..sa/99 1,172,601 2/1916 Jaques n ..58/95 R 2,228,681 1/1941 Wagner ..5,8/99

FOREIGN PATENTS OR APPLICATIONS 71,945 7/1915 Switzerland ..95 R

Primary Examiner-George H. Miller, Jr. Attorney-Alex Friedman et al.

I I [57] ABSTRACT A watch stem in a calendar watch has a number of grooves thereon. One end of a spring, fastened at the ,other end to a base plate, is seated resiliently in one of the grooves. Movement of the watch stem in an axial direction requires that the seated end of the spring ride up on the walls of the grooves which are tapered. The resistance which must be overcome in moving the watch stem from one position to another can be varied by changing the angle of the'groove walls and by changing the height of the walls between adjacent grooves.

4 Claims, 2 Drawing Figures PATENTEDJANZ ms 3. 707.840

FIG.

INVENTOR. MAMORU MIYASAKA ATTORNEYS STEM CONSTRUCTION IN A CALENDAR WATCH BACKGROUND OF THE INVENTION In the conventional construction of a watch, the resistance to movement of the watch stem from one position to another is exerted by a spring lever which presses against a setting lever pin. The spring-mounted lever has a number of grooves therein, into any one of which the pin of the setting lever can be moved. To move from one groove to an adjacent groove, the pin must climb one wall of the groove and lodge in the next groove. The force which must be exerted to move the watch stem from one position to another, involving transfer of the pin from one groove to the next, depends on the height of the wall which must be climbed and the steepness of the wall.

The calendar watch which has recently become so popular, requires several steps in the movement of the crown for adjustment of the day, date and the time and for winding the watch. It is desirable that the operator should be able to discriminate between the force necessary to pass from the first step to the second step and from the second step to the third step. For example, in a conventional watch, the force required for going from the first step to the second step may be 300g whereas the force necessary to go from the second step to the third step may be 800g. This differentiation is made possible by proper selection of the heights of the peaks between the grooves and by varying the steepness of the groove walls. However, as the height of the peaks is increased, the distance through which the pin of the setting lever must travel is correspondingly made larger. As a result, the angle through which the setting lever must rotate is increased. Consequently the space required by these larger elements and for increased distances to be traversed, is increased. This is a serious disadvantage since minimization of the size of a watch is always an objective to be striven for. In addition, the suggested changes in the contours of the members increases the likelihood of breakage; furthermore, the

ponents is difficult to make.

SUMMARY OF THE INVENTION To provide for movement of a watch stem to any of a plurality of positions, a corresponding number of annular grooves are formed in the watch stem. The watch stem is mounted for axial as well as rotational movement on a base plate, and a spring, at least-part of which is sheet-like in form is also mounted on the base plate in such a relationship to thewatch stem that one end of the spring can be seated resiliently in any of the grooves. The watch stem can be moved in an axial direction by exerting enough force thereon to cause the resiliently seated end of the watch spring to move outwardly from the axis of the watch stem as the wall of the groove passes thereunder. As the motion continues, the spring then seats in the next groove. The force required to move the watch stem from one position to the next is established by controlling the steepness of the groove walls and the height of said walls.

Accordingly, an object of the present invention is to provide a simple construction for a watch stem movable to any of a plurality of positions.

' will in part be obvious and will in part be apparent from the specification.

The invention accordingly comprises the feature of construction, combination of elements, and arrangement of parts which will be exemplified in the construc-- tion hereinafter set forth, and the scope of the invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWING For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawing, in which:

FIG. 1 is an enlarged partial view in plan of a watch setting mechanism in accordance with the present invention; and

FIG. 2 is a side view in elevation of the same mechanism.

DESCRIPTION OF THEIPREFERRED EMBODIMENT Thesetting mechanism for a calendar watch in accordance with the present invention comprises a watch stem 5 having grooves 6 therein separated by peaks 7. A spring 8 is fastened to a base plate 9 which also supports the stem 5. At least that portion of the spring 8 indicated by the reference number 10 is of thin, sheetlike construction; the resiliency of the spring 8 is due to the flexibility in a transverse direction of the portion To move the watch stem from one position to the next, enough force must be exerted in an axial direction to cause the spring 8 to climb one wall of the groove in which it is lodged and to climb over the peak to the next groove. If the height of the peak, this corresponding to the outer diameter of the corresponding land, is increased, the force which must be exerted to cause a change in position is likewise increased due to two factors; these two factors are the steepness of the wall and the height of the peak. The effect of the wall steepness on the necessary force is primarily due to friction. The,

effect of the peak height is to increase the peak force to a quantity proportional to the height of the peak as measured from the axis of the stem. a

By proper selection of these two factors the difference in the forces necessary to pass from one step to another and then onto still another can be made readily perceptible to the operator. In general, it is desirable that the force increase with each successive step.

The construction described makes it easy to adjust the force required for movement of the stern by adjustment of a cutting tool. Also, since the spring is bent in the direction of its thickness, the size of the spring may be increased making it sturdy and easy to manufacture. Moreover, both radial and axial play of the stem are eliminated, the various stem positions are sharply located, the number of parts required for the construction is decreased and the space for the entire mechanism is reduced. These features are effective in decreasing the overall size of the system and in reducing the cost, particularly in large scale manufacture.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

What is claimed is:

l. A construction for holding a watch stem in a Watch at any of at least three positions with respect to said watch, comprising a watch stern having thereon at least three annular grooves, and spring means adapted to seat resiliently in any of said grooves, at least a portion of said spring means being sheet-like in form, and positioned to flex transversely of said sheet-like portion for holding said watch stem in any of said positions and permitting manually effected alteration of the position of said watch stem inwardly or outwardly of said watch by causing said spring means to move over the surfaces of said sloping walls away from and toward the axis of said stem, the walls of said grooves sloping at different angles.

2. The construction as defined in claim 1, wherein said watch stem has a crown wherein the angle of the wall and the height of the peak between each successive pair of grooves increases with distance from the crown.

3. A construction for holding a watch stem in a watch at any of at least three positions with respect to said watch, comprising a watch stern having thereon at least three annular grooves, and spring means adapted to seat resiliently in any of said grooves, at least a portion of said spring means being sheet-like in form, and positioned to flex transversely of said sheet-like portion for holding said watch stem in any of said positions and permitting manually effected alteration of the position of said watch stem inwardly or outwardly of said watch by causing said spring means to move over the surfaces of said sloping walls away from and toward the axis of said stem, the peaks between said grooves being of different heights.

4. The construction as defined in claim 3, wherein said walls of said plurality of grooves slope at different angles and said peaks have different heights. 

1. A construction for holding a watch stem in a watch at any of at least three positions with respect to said watch, comprising a watch stem having thereon at least three annular grooves, and spring means adapted to seat resiliently in any of said grooves, at least a portion of said spring means being sheet-like in form, and positioned to flex transversely of said sheet-like portion for holding said watch stem in any of said positions and permitting manually effected alteration of the position of said watch stem inwardly or outwardly of said watch by causing said spring means to move over the surfaces of said sloping walls away from and toward the axis of said stem, the walls of said grooves sloping at different angles.
 2. The construction as defined in claim 1, wherein said watch stem has a crown wherein the angle of the wall and the height of the peak between each successive pair of grooves increases with distance from the crown.
 3. A construction for holding a watch stem in a watch at any of at least three positions with respect to said watch, comprising a watch stem having thereon at least three annular grooves, and spring means adapted to seat resiliently in any of said grooves, at least a portion of said spring means being sheet-like in form, and positioned to flex transversely of said sheet-like portion for holding said watch stem in any of said positions and permitting manually effected alteration of the position of said watch stem inwardly or outwardly of said watch by causing said spring means to move over the surfaces of said sloping walls away from and toward the axis of said stem, the peaks between said grooves being of different heights.
 4. The construction as defined in claim 3, wherein said walls of said plurality of grooves slope at different angles and said peaks have different heights. 